Mk3 103tsi consumption at tickover

[Gerrycan]

I would like confirmation from other 1.4tsi users of the instant fuel consumption read-out for the tickover when you first start your car from cold.
My car shows 2.4 to 2.6 l/hour. That is with an ambient temperature of 26 deg C, no lights, fans or a/c on.

After only a kilometre of driving the tickover consumption has dropped to 0.7 to 0.8 l/hour and shortly after that it will read the normal 0.4 to 0.5 l/hour.
I don't really need that secondary info confirmed but thought it might interest others as to how quickly it warms up.

I am trying to determine if the cold start consumption is normal as this phase is when I experience in-gear low rev/speed hesitation and poor throttle response.

Thanks

Gerry

[kaanage]

Yes, it's normal.

The ECU will run the car far richer than normal (keep throttle plate more closed, inject more fuel) when cold to drive against the thicker oil. It will not produce anywhere near optimal power delivery in this mode hence the poor driving characteristics.

With carbys, this was done via the choke (basically another throttle plate upstream of the normal one and jets)

[Gerrycan]

I know that more fuel is required for the cold start process but I am trying to compare the actual amount required for a car that is not experiencing cold start driving issues that I am.
My car is less than a year old and it did not have these problems for the first 2k so there is something wrong and I want it fixed.
I have already left it with the dealers and got the usual and totally unsatisfactory "it's normal" response.
I need facts to ascertain if my readings are relatively rich or lean, or even normal for this phase.

[brad]

It's probably worth your while to ask about the experience of 90tsi Golf owners. The fuel mapping would be very similar.

[GTR27]

I know that more fuel is required for the cold start process but I am trying to compare the actual amount required for a car that is not experiencing cold start driving issues that I am.
My car is less than a year old and it did not have these problems for the first 2k so there is something wrong and I want it fixed.
I have already left it with the dealers and got the usual and totally unsatisfactory "it's normal" response.
I need facts to ascertain if my readings are relatively rich or lean, or even normal for this phase.

Does yours have the mode button Gerry? Does it do it in all modes?

[brenno]

Mine goes up to 3.7l/hour on a cold start.

I've sent you a PM with a video, Gerry.

[Gerrycan]

Does yours have the mode button Gerry? Does it do it in all modes?

Lol, it's an Ambition, it only has one mode.

[Gerrycan]

Mine goes up to 3.7l/hour on a cold start.

I've sent you a PM with a video, Gerry.

Well that was interesting!
I did what Brenno did in his video he sent to me and started the engine and just let it idle until more normal tickover rpm and consumption figures (this time went from 4.4 l/hour down to around 0.7 to 0.9 l/hour). It took about 45 seconds.
Then I pulled out the garage into the drive and did my usual 1st gear crawl to the end of the driveway AND I DID NOT EXPERIENCE THE HESITATION and throttle response seemed normal.

I never idle after starting, I just start and go. Of course I got told off by my Eco-tips display about unnecessary idling affecting fuel consumption when I did it.

I must be confusing the ECU? more experimentation required, but I can only do it once a day on the first cold start.

[GTR27]

Lol, it's an Ambition, it only has one mode.

I just took a vid of stone cold start of ours. Im currently uploading it to youtube.

TLDR; 3.1 L/hr on initial start, then drops to 2.7-2.8, then down to ~2L/hr very quickly. I shut it off after that. 27.5 deg ambient (according to car)

YouTube

EDIT: The mode button is a wank anyway, ours stays in normal all the time. I just have steering in "sport" for a bit more weight to it

[Gerrycan]

It's probably worth your while to ask about the experience of 90tsi Golf owners. The fuel mapping would be very similar.

Agree, but I did not need that many responses just a couple to compare.

Brenno has come up with 'beyond the call of duty response' that has lead to an interesting discovery for me.